Technical Field
The present invention relates to an electronic device, and in particular, to a buffer circuit used in the electronic device.
Related Art
Buffers are widely used in various electronic devices for timing, driving and so on. In some cases, such as in a clock tree, driving of different levels are required due to more and more complicated designs. FIG. 1 illustrates an example of a buffer cascade including two levels of buffers. A buffer usually includes an inverter, and the output driving capability of the buffer merely depends on tube properties of the output level, and is irrelevant to a logic state of each input terminal. The higher level the buffer is in, the more the energy it consumes because more units are to be driven. Therefore, greater driving capability is required.
However, as the number of the levels goes higher, time delay and power consumption also increase sharply. The higher the level, the greater the demands on the driving capability is because an increased number of components are to be driven, hence the greater the power consumption. The result of a peak current increase may be that an instantaneous peak current/voltage surpasses the capacity of the power source and leads to component damage, functional failure, and so on.